The invention relates to keyboards and more particularly to keyboards having elongate keys and still more particularly to electrical switch mechanisms operated by such keys.
I have previously proposed, in my prior U.S. Pat. No. 4,449,839 issued May 22, 1984, a keyboard with elongate integral keys each of which has a longitudinal row of three finger receiving recesses and actuating switch mechanism so that, when the key is depressed using the central recess, one switch is actuated; while, if the two end recesses are used, a pair of other switches are actuated respectively. The switch mechanism for each of the keys includes a cylindrical plunger about which a return spring is disposed and swingingly mounting the key and a pair of contacting plate portions on one side of the plunger one of which is fixed and the other of which carries a switch actuating pin for actuating three different switches depending on whether the key is depressed without swinging motion or with swinging motion in opposite directions.